/*
 * Dirent interface for Microsoft Visual Studio
 * Version 1.21
 *
 * Copyright (C) 2006-2012 Toni Ronkko
 * This file is part of dirent.  Dirent may be freely distributed
 * under the MIT license.  For all details and documentation, see
 * https://github.com/tronkko/dirent
 */
#pragma once

/*
 * Include windows.h without Windows Sockets 1.1 to prevent conflicts with
 * Windows Sockets 2.0.
 */
#ifndef WIN32_LEAN_AND_MEAN
#	define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>

#include <stdio.h>
#include <stdarg.h>
#include <wchar.h>
#include <string.h>
#include <stdlib.h>
#include <malloc.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>

/* Indicates that d_type field is available in dirent structure */
#define _DIRENT_HAVE_D_TYPE

/* Indicates that d_namlen field is available in dirent structure */
#define _DIRENT_HAVE_D_NAMLEN

/* Entries missing from MSVC 6.0 */
#if !defined(FILE_ATTRIBUTE_DEVICE)
#	define FILE_ATTRIBUTE_DEVICE 0x40
#endif

/* File type and permission flags for stat(), general mask */
#if !defined(S_IFMT)
#	define S_IFMT _S_IFMT
#endif

/* Directory bit */
#if !defined(S_IFDIR)
#	define S_IFDIR _S_IFDIR
#endif

/* Character device bit */
#if !defined(S_IFCHR)
#	define S_IFCHR _S_IFCHR
#endif

/* Pipe bit */
#if !defined(S_IFFIFO)
#	define S_IFFIFO _S_IFFIFO
#endif

/* Regular file bit */
#if !defined(S_IFREG)
#	define S_IFREG _S_IFREG
#endif

/* Read permission */
#if !defined(S_IREAD)
#	define S_IREAD _S_IREAD
#endif

/* Write permission */
#if !defined(S_IWRITE)
#	define S_IWRITE _S_IWRITE
#endif

/* Execute permission */
#if !defined(S_IEXEC)
#	define S_IEXEC _S_IEXEC
#endif

/* Pipe */
#if !defined(S_IFIFO)
#	define S_IFIFO _S_IFIFO
#endif

/* Block device */
#if !defined(S_IFBLK)
#	define S_IFBLK 0
#endif

/* Link */
#if !defined(S_IFLNK)
#	define S_IFLNK 0
#endif

/* Socket */
#if !defined(S_IFSOCK)
#	define S_IFSOCK 0
#endif

/* Read user permission */
#if !defined(S_IRUSR)
#	define S_IRUSR S_IREAD
#endif

/* Write user permission */
#if !defined(S_IWUSR)
#	define S_IWUSR S_IWRITE
#endif

/* Execute user permission */
#if !defined(S_IXUSR)
#	define S_IXUSR 0
#endif

/* Read group permission */
#if !defined(S_IRGRP)
#	define S_IRGRP 0
#endif

/* Write group permission */
#if !defined(S_IWGRP)
#	define S_IWGRP 0
#endif

/* Execute group permission */
#if !defined(S_IXGRP)
#	define S_IXGRP 0
#endif

/* Read others permission */
#if !defined(S_IROTH)
#	define S_IROTH 0
#endif

/* Write others permission */
#if !defined(S_IWOTH)
#	define S_IWOTH 0
#endif

/* Execute others permission */
#if !defined(S_IXOTH)
#	define S_IXOTH 0
#endif

/* Maximum length of file name */
#if !defined(PATH_MAX)
#	define PATH_MAX MAX_PATH
#endif
#if !defined(FILENAME_MAX)
#	define FILENAME_MAX MAX_PATH
#endif
#if !defined(NAME_MAX)
#	define NAME_MAX FILENAME_MAX
#endif

/* File type flags for d_type */
#define DT_UNKNOWN 0
#define DT_REG S_IFREG
#define DT_DIR S_IFDIR
#define DT_FIFO S_IFIFO
#define DT_SOCK S_IFSOCK
#define DT_CHR S_IFCHR
#define DT_BLK S_IFBLK
#define DT_LNK S_IFLNK

/* Macros for converting between st_mode and d_type */
#define IFTODT(mode) ((mode) & S_IFMT)
#define DTTOIF(type) (type)

/*
 * File type macros.  Note that block devices, sockets and links cannot be
 * distinguished on Windows and the macros S_ISBLK, S_ISSOCK and S_ISLNK are
 * only defined for compatibility.  These macros should always return false
 * on Windows.
 */
#if !defined(S_ISFIFO)
#	define S_ISFIFO(mode) (((mode) & S_IFMT) == S_IFIFO)
#endif
#if !defined(S_ISDIR)
#	define S_ISDIR(mode) (((mode) & S_IFMT) == S_IFDIR)
#endif
#if !defined(S_ISREG)
#	define S_ISREG(mode) (((mode) & S_IFMT) == S_IFREG)
#endif
#if !defined(S_ISLNK)
#	define S_ISLNK(mode) (((mode) & S_IFMT) == S_IFLNK)
#endif
#if !defined(S_ISSOCK)
#	define S_ISSOCK(mode) (((mode) & S_IFMT) == S_IFSOCK)
#endif
#if !defined(S_ISCHR)
#	define S_ISCHR(mode) (((mode) & S_IFMT) == S_IFCHR)
#endif
#if !defined(S_ISBLK)
#	define S_ISBLK(mode) (((mode) & S_IFMT) == S_IFBLK)
#endif

/* Return the exact length of d_namlen without zero terminator */
#define _D_EXACT_NAMLEN(p) ((p)->d_namlen)

/* Return number of bytes needed to store d_namlen */
#define _D_ALLOC_NAMLEN(p) (PATH_MAX)

#ifdef __cplusplus
extern "C"
{
#endif

	/* Wide-character version */
	struct _wdirent
	{
		/* Always zero */
		long d_ino;

		/* Structure size */
		unsigned short d_reclen;

		/* Length of name without \0 */
		size_t d_namlen;

		/* File type */
		int d_type;

		/* File name */
		wchar_t d_name[PATH_MAX];
	};
	typedef struct _wdirent _wdirent;

	struct _WDIR
	{
		/* Current directory entry */
		struct _wdirent ent;

		/* Private file data */
		WIN32_FIND_DATAW data;

		/* True if data is valid */
		int cached;

		/* Win32 search handle */
		HANDLE handle;

		/* Initial directory name */
		wchar_t* patt;
	};
	typedef struct _WDIR _WDIR;

	static _WDIR* _wopendir(const wchar_t* dirname);
	static struct _wdirent* _wreaddir(_WDIR* dirp);
	static int _wclosedir(_WDIR* dirp);
	static void _wrewinddir(_WDIR* dirp);

/* For compatibility with Symbian */
#define wdirent _wdirent
#define WDIR _WDIR
#define wopendir _wopendir
#define wreaddir _wreaddir
#define wclosedir _wclosedir
#define wrewinddir _wrewinddir

	/* Multi-byte character versions */
	struct dirent
	{
		/* Always zero */
		long d_ino;

		/* Structure size */
		unsigned short d_reclen;

		/* Length of name without \0 */
		size_t d_namlen;

		/* File type */
		int d_type;

		/* File name */
		char d_name[PATH_MAX];
	};
	typedef struct dirent dirent;

	struct DIR
	{
		struct dirent ent;
		struct _WDIR* wdirp;
	};
	typedef struct DIR DIR;

	static DIR* opendir(const char* dirname);
	static struct dirent* readdir(DIR* dirp);
	static int closedir(DIR* dirp);
	static void rewinddir(DIR* dirp);

	/* Internal utility functions */
	static WIN32_FIND_DATAW* dirent_first(_WDIR* dirp);
	static WIN32_FIND_DATAW* dirent_next(_WDIR* dirp);

	static int dirent_mbstowcs_s(size_t* pReturnValue, wchar_t* wcstr, size_t sizeInWords, const char* mbstr,
	                             size_t count);

	static int dirent_wcstombs_s(size_t* pReturnValue, char* mbstr, size_t sizeInBytes, const wchar_t* wcstr,
	                             size_t count);

	static void dirent_set_errno(int error);

	/*
	 * Open directory stream DIRNAME for read and return a pointer to the
	 * internal working area that is used to retrieve individual directory
	 * entries.
	 */
	static _WDIR* _wopendir(const wchar_t* dirname)
	{
		_WDIR* dirp = NULL;
		int error;

		/* Must have directory name */
		if (dirname == NULL || dirname[0] == '\0')
		{
			dirent_set_errno(ENOENT);
			return NULL;
		}

		/* Allocate new _WDIR structure */
		dirp = (_WDIR*)malloc(sizeof(struct _WDIR));
		if (dirp != NULL)
		{
			DWORD n;

			/* Reset _WDIR structure */
			dirp->handle = INVALID_HANDLE_VALUE;
			dirp->patt = NULL;
			dirp->cached = 0;

			/* Compute the length of full path plus zero terminator
			 *
			 * Note that on WinRT there's no way to convert relative paths
			 * into absolute paths, so just assume its an absolute path.
			 */
#if defined(WINAPI_FAMILY) && (WINAPI_FAMILY == WINAPI_FAMILY_PHONE_APP)
			n = wcslen(dirname);
#else
		n = GetFullPathNameW(dirname, 0, NULL, NULL);
#endif

			/* Allocate room for absolute directory name and search pattern */
			dirp->patt = (wchar_t*)malloc(sizeof(wchar_t) * n + 16);
			if (dirp->patt)
			{

				/*
				 * Convert relative directory name to an absolute one.  This
				 * allows rewinddir() to function correctly even when current
				 * working directory is changed between opendir() and rewinddir().
				 *
				 * Note that on WinRT there's no way to convert relative paths
				 * into absolute paths, so just assume its an absolute path.
				 */
#if defined(WINAPI_FAMILY) && (WINAPI_FAMILY == WINAPI_FAMILY_PHONE_APP)
				wcsncpy_s(dirp->patt, n + 1, dirname, n);
#else
			n = GetFullPathNameW(dirname, n, dirp->patt, NULL);
#endif
				if (n > 0)
				{
					wchar_t* p;

					/* Append search pattern \* to the directory name */
					p = dirp->patt + n;
					if (dirp->patt < p)
					{
						switch (p[-1])
						{
						case '\\':
						case '/':
						case ':':
						    /* Directory ends in path separator, e.g. c:\temp\ */
						    /*NOP*/;
							break;

						default:
							/* Directory name doesn't end in path separator */
							*p++ = '\\';
						}
					}
					*p++ = '*';
					*p = '\0';

					/* Open directory stream and retrieve the first entry */
					if (dirent_first(dirp))
					{
						/* Directory stream opened successfully */
						error = 0;
					}
					else
					{
						/* Cannot retrieve first entry */
						error = 1;
						dirent_set_errno(ENOENT);
					}
				}
				else
				{
					/* Cannot retrieve full path name */
					dirent_set_errno(ENOENT);
					error = 1;
				}
			}
			else
			{
				/* Cannot allocate memory for search pattern */
				error = 1;
			}
		}
		else
		{
			/* Cannot allocate _WDIR structure */
			error = 1;
		}

		/* Clean up in case of error */
		if (error && dirp)
		{
			_wclosedir(dirp);
			dirp = NULL;
		}

		return dirp;
	}

	/*
	 * Read next directory entry.  The directory entry is returned in dirent
	 * structure in the d_name field.  Individual directory entries returned by
	 * this function include regular files, sub-directories, pseudo-directories
	 * "." and ".." as well as volume labels, hidden files and system files.
	 */
	static struct _wdirent* _wreaddir(_WDIR* dirp)
	{
		WIN32_FIND_DATAW* datap;
		struct _wdirent* entp;

		/* Read next directory entry */
		datap = dirent_next(dirp);
		if (datap)
		{
			size_t n;
			DWORD attr;

			/* Pointer to directory entry to return */
			entp = &dirp->ent;

			/*
			 * Copy file name as wide-character string.  If the file name is too
			 * long to fit in to the destination buffer, then truncate file name
			 * to PATH_MAX characters and zero-terminate the buffer.
			 */
			n = 0;
			while (n + 1 < PATH_MAX && datap->cFileName[n] != 0)
			{
				entp->d_name[n] = datap->cFileName[n];
				n++;
			}
			dirp->ent.d_name[n] = 0;

			/* Length of file name excluding zero terminator */
			entp->d_namlen = n;

			/* File type */
			attr = datap->dwFileAttributes;
			if ((attr & FILE_ATTRIBUTE_DEVICE) != 0)
			{
				entp->d_type = DT_CHR;
			}
			else if ((attr & FILE_ATTRIBUTE_DIRECTORY) != 0)
			{
				entp->d_type = DT_DIR;
			}
			else
			{
				entp->d_type = DT_REG;
			}

			/* Reset dummy fields */
			entp->d_ino = 0;
			entp->d_reclen = sizeof(struct _wdirent);
		}
		else
		{

			/* Last directory entry read */
			entp = NULL;
		}

		return entp;
	}

	/*
	 * Close directory stream opened by opendir() function.  This invalidates the
	 * DIR structure as well as any directory entry read previously by
	 * _wreaddir().
	 */
	static int _wclosedir(_WDIR* dirp)
	{
		int ok;
		if (dirp)
		{

			/* Release search handle */
			if (dirp->handle != INVALID_HANDLE_VALUE)
			{
				FindClose(dirp->handle);
				dirp->handle = INVALID_HANDLE_VALUE;
			}

			/* Release search pattern */
			if (dirp->patt)
			{
				free(dirp->patt);
				dirp->patt = NULL;
			}

			/* Release directory structure */
			free(dirp);
			ok = /*success*/ 0;
		}
		else
		{
			/* Invalid directory stream */
			dirent_set_errno(EBADF);
			ok = /*failure*/ -1;
		}
		return ok;
	}

	/*
	 * Rewind directory stream such that _wreaddir() returns the very first
	 * file name again.
	 */
	static void _wrewinddir(_WDIR* dirp)
	{
		if (dirp)
		{
			/* Release existing search handle */
			if (dirp->handle != INVALID_HANDLE_VALUE)
			{
				FindClose(dirp->handle);
			}

			/* Open new search handle */
			dirent_first(dirp);
		}
	}

	/* Get first directory entry (internal) */
	static WIN32_FIND_DATAW* dirent_first(_WDIR* dirp)
	{
		WIN32_FIND_DATAW* datap;

		/* Open directory and retrieve the first entry */
		dirp->handle = FindFirstFileExW(dirp->patt, FindExInfoStandard, &dirp->data, FindExSearchNameMatch, NULL, 0);
		if (dirp->handle != INVALID_HANDLE_VALUE)
		{

			/* a directory entry is now waiting in memory */
			datap = &dirp->data;
			dirp->cached = 1;
		}
		else
		{

			/* Failed to re-open directory: no directory entry in memory */
			dirp->cached = 0;
			datap = NULL;
		}
		return datap;
	}

	/* Get next directory entry (internal) */
	static WIN32_FIND_DATAW* dirent_next(_WDIR* dirp)
	{
		WIN32_FIND_DATAW* p;

		/* Get next directory entry */
		if (dirp->cached != 0)
		{

			/* A valid directory entry already in memory */
			p = &dirp->data;
			dirp->cached = 0;
		}
		else if (dirp->handle != INVALID_HANDLE_VALUE)
		{

			/* Get the next directory entry from stream */
			if (FindNextFileW(dirp->handle, &dirp->data) != FALSE)
			{
				/* Got a file */
				p = &dirp->data;
			}
			else
			{
				/* The very last entry has been processed or an error occurred */
				FindClose(dirp->handle);
				dirp->handle = INVALID_HANDLE_VALUE;
				p = NULL;
			}
		}
		else
		{

			/* End of directory stream reached */
			p = NULL;
		}

		return p;
	}

	/*
	 * Open directory stream using plain old C-string.
	 */
	static DIR* opendir(const char* dirname)
	{
		struct DIR* dirp;
		int error;

		/* Must have directory name */
		if (dirname == NULL || dirname[0] == '\0')
		{
			dirent_set_errno(ENOENT);
			return NULL;
		}

		/* Allocate memory for DIR structure */
		dirp = (DIR*)malloc(sizeof(struct DIR));
		if (dirp)
		{
			wchar_t wname[PATH_MAX];
			size_t n;

			/* Convert directory name to wide-character string */
			error = dirent_mbstowcs_s(&n, wname, PATH_MAX, dirname, PATH_MAX);
			if (!error)
			{

				/* Open directory stream using wide-character name */
				dirp->wdirp = _wopendir(wname);
				if (dirp->wdirp)
				{
					/* Directory stream opened */
					error = 0;
				}
				else
				{
					/* Failed to open directory stream */
					error = 1;
				}
			}
			else
			{
				/*
				 * Cannot convert file name to wide-character string.  This
				 * occurs if the string contains invalid multi-byte sequences or
				 * the output buffer is too small to contain the resulting
				 * string.
				 */
				error = 1;
			}
		}
		else
		{
			/* Cannot allocate DIR structure */
			error = 1;
		}

		/* Clean up in case of error */
		if (error && dirp)
		{
			free(dirp);
			dirp = NULL;
		}

		return dirp;
	}

	/*
	 * Read next directory entry.
	 *
	 * When working with text consoles, please note that file names returned by
	 * readdir() are represented in the default ANSI code page while any output to
	 * console is typically formatted on another code page.  Thus, non-ASCII
	 * characters in file names will not usually display correctly on console.  The
	 * problem can be fixed in two ways: (1) change the character set of console
	 * to 1252 using chcp utility and use Lucida Console font, or (2) use
	 * _cprintf function when writing to console.  The _cprinf() will re-encode
	 * ANSI strings to the console code page so many non-ASCII characters will
	 * display correctly.
	 */
	static struct dirent* readdir(DIR* dirp)
	{
		WIN32_FIND_DATAW* datap;
		struct dirent* entp;

		/* Read next directory entry */
		datap = dirent_next(dirp->wdirp);
		if (datap)
		{
			size_t n;
			int error;

			/* Attempt to convert file name to multi-byte string */
			error = dirent_wcstombs_s(&n, dirp->ent.d_name, PATH_MAX, datap->cFileName, PATH_MAX);

			/*
			 * If the file name cannot be represented by a multi-byte string,
			 * then attempt to use old 8+3 file name.  This allows traditional
			 * Unix-code to access some file names despite of unicode
			 * characters, although file names may seem unfamiliar to the user.
			 *
			 * Be ware that the code below cannot come up with a short file
			 * name unless the file system provides one.  At least
			 * VirtualBox shared folders fail to do this.
			 */
			if (error && datap->cAlternateFileName[0] != '\0')
			{
				error = dirent_wcstombs_s(&n, dirp->ent.d_name, PATH_MAX, datap->cAlternateFileName, PATH_MAX);
			}

			if (!error)
			{
				DWORD attr;

				/* Initialize directory entry for return */
				entp = &dirp->ent;

				/* Length of file name excluding zero terminator */
				entp->d_namlen = n - 1;

				/* File attributes */
				attr = datap->dwFileAttributes;
				if ((attr & FILE_ATTRIBUTE_DEVICE) != 0)
				{
					entp->d_type = DT_CHR;
				}
				else if ((attr & FILE_ATTRIBUTE_DIRECTORY) != 0)
				{
					entp->d_type = DT_DIR;
				}
				else
				{
					entp->d_type = DT_REG;
				}

				/* Reset dummy fields */
				entp->d_ino = 0;
				entp->d_reclen = sizeof(struct dirent);
			}
			else
			{
				/*
				 * Cannot convert file name to multi-byte string so construct
				 * an erroneous directory entry and return that.  Note that
				 * we cannot return NULL as that would stop the processing
				 * of directory entries completely.
				 */
				entp = &dirp->ent;
				entp->d_name[0] = '?';
				entp->d_name[1] = '\0';
				entp->d_namlen = 1;
				entp->d_type = DT_UNKNOWN;
				entp->d_ino = 0;
				entp->d_reclen = 0;
			}
		}
		else
		{
			/* No more directory entries */
			entp = NULL;
		}

		return entp;
	}

	/*
	 * Close directory stream.
	 */
	static int closedir(DIR* dirp)
	{
		int ok;
		if (dirp)
		{

			/* Close wide-character directory stream */
			ok = _wclosedir(dirp->wdirp);
			dirp->wdirp = NULL;

			/* Release multi-byte character version */
			free(dirp);
		}
		else
		{

			/* Invalid directory stream */
			dirent_set_errno(EBADF);
			ok = /*failure*/ -1;
		}
		return ok;
	}

	/*
	 * Rewind directory stream to beginning.
	 */
	static void rewinddir(DIR* dirp)
	{
		/* Rewind wide-character string directory stream */
		_wrewinddir(dirp->wdirp);
	}

	/* Convert multi-byte string to wide character string */
	static int dirent_mbstowcs_s(size_t* pReturnValue, wchar_t* wcstr, size_t sizeInWords, const char* mbstr,
	                             size_t count)
	{
		int error;

#if defined(_MSC_VER) && _MSC_VER >= 1400

		/* Microsoft Visual Studio 2005 or later */
		error = mbstowcs_s(pReturnValue, wcstr, sizeInWords, mbstr, count);

#else

	/* Older Visual Studio or non-Microsoft compiler */
	size_t n;

	/* Convert to wide-character string (or count characters) */
	n = mbstowcs(wcstr, mbstr, sizeInWords);
	if (!wcstr || n < count)
	{

		/* Zero-terminate output buffer */
		if (wcstr && sizeInWords)
		{
			if (n >= sizeInWords)
			{
				n = sizeInWords - 1;
			}
			wcstr[n] = 0;
		}

		/* Length of resuting multi-byte string WITH zero terminator */
		if (pReturnValue)
		{
			*pReturnValue = n + 1;
		}

		/* Success */
		error = 0;
	}
	else
	{

		/* Could not convert string */
		error = 1;
	}

#endif

		return error;
	}

	/* Convert wide-character string to multi-byte string */
	static int dirent_wcstombs_s(size_t* pReturnValue, char* mbstr, size_t sizeInBytes, /* max size of mbstr */
	                             const wchar_t* wcstr, size_t count)
	{
		int error;

#if defined(_MSC_VER) && _MSC_VER >= 1400

		/* Microsoft Visual Studio 2005 or later */
		error = wcstombs_s(pReturnValue, mbstr, sizeInBytes, wcstr, count);

#else

	/* Older Visual Studio or non-Microsoft compiler */
	size_t n;

	/* Convert to multi-byte string (or count the number of bytes needed) */
	n = wcstombs(mbstr, wcstr, sizeInBytes);
	if (!mbstr || n < count)
	{

		/* Zero-terminate output buffer */
		if (mbstr && sizeInBytes)
		{
			if (n >= sizeInBytes)
			{
				n = sizeInBytes - 1;
			}
			mbstr[n] = '\0';
		}

		/* Length of resulting multi-bytes string WITH zero-terminator */
		if (pReturnValue)
		{
			*pReturnValue = n + 1;
		}

		/* Success */
		error = 0;
	}
	else
	{

		/* Cannot convert string */
		error = 1;
	}

#endif

		return error;
	}

	/* Set errno variable */
	static void dirent_set_errno(int error)
	{
#if defined(_MSC_VER) && _MSC_VER >= 1400

		/* Microsoft Visual Studio 2005 and later */
		_set_errno(error);

#else

	/* Non-Microsoft compiler or older Microsoft compiler */
	errno = error;

#endif
	}

#ifdef __cplusplus
}
#endif
